var k = document.getElementById("k");

function san(a) {
    if (k.innerText == "0") {
        k.innerText = "";
    }
    k.innerText += a;
}

function ab() {
    k.innerText = eval(k.innerText).toFixed(2);
}

function AC() {
    k.innerText = "0";
}

function X2() {
    k.innerText = eval(k.innerText * k.innerText).toFixed(2);
}

function X3() {
    k.innerText = eval(k.innerText * k.innerText * k.innerText).toFixed(2);
}